1. Field of the Invention
The present invention relates generally to an low-insertion-force (hereinafter LIF) connector having an actuator for adjusting the strength of the connection between the contacts of a jack and the pins of a plug.
2. Description of the Related Art
In recent years, with the increasing density of substrate circuitry and the greater number of signal lines required by an increasing array of functions, the number of pins on the connectors of the substrates of communications devices, personal computers, workstations, large-scale calculators and the like has also increased. As a result, connectors into which multi-pin jacks and plugs are inserted require substantial force both to insert and to remove the jacks and plugs inserted therein. In such a situation, an LIF connector capable of opening or closing the connectors as appropriate and permitting the insertion and removal of even a multi-pin plug with a minimum amount of force is used.
FIG. 1 is a diagram of the structure of a conventional LIF connector. It should be noted that FIG. 1 depicts only the jack portion of the connector.
The conventional LIF connector jack portion 101 comprises, for example, a jack base 102 in a state in which pins 106 for connection to the substrate are mounted on a bottom part and contacts 105 for inserting the pins of the plug portion are mounted on a top part, an actuator 103 for adjusting the strength of the connection between the pins of the plug and the contacts 105 by being moved up or down with respect to the base, and a jack cover 104 made of an insulating material for the purpose of preventing trouble such as a short circuiting caused by contact from external parts.
FIGS. 2(A), 2(B) and 2(C) show external top, front and side views, respectively, of the-jack portion 101 in a state of being mounted on a substrate 111. Normally, pins 106 for connection to the substrate are mounted and, as shown in the diagram, the pins 106 are inserted into through-holes in the substrate and soldered. Additionally, a slanted slot 112 is formed in the actuator and is used when adjusting the strength of the connection of the pins of the plug with the contacts 105.
FIGS. 3(A) and 3(B) show top and side views, respectively, of a state in which an LIF connector tool is further mounted on the LIF connector depicted in FIG. 2. As shown in the diagram, the LIF connector tool comprises an operating member 121, an engaging portion 122 and a slide cam 123, with the slide cam 123 positioned so as to sandwich the jack portion 101.
FIGS. 4(A) and 4(B) show how the actuator 103 is moved by the LIF connector tool depicted in FIG. 3. Initially, a projection 124 provided on a side surface of the slide cam 123 facing the jack 101 is accommodated at a predetermined initial position of a slot 112 in the actuator 103, as shown in FIG. 4(A). Additionally, when the projection 124 is at that initial position, as shown in FIG. 3(A) and also in FIG. 4(A), the operating member 121 is perpendicular to the plane of the slide cam 123, the actuator 103 is positioned at a maximum low position and the contacts 105 of the jack portion 101 are opened. At this stage the strength of connection at the contacts 105 is at its weakest.
It is in such a state that by gradually depressing the operating member 121 toward the jack portion 101 that the teeth of the gears of the engaging portion 122 mesh, gradually drawing the slide cam 123 toward the engaging portion 122. At the same time, the projection 124 of the slide cam 123 accommodated within the slot 112 moves gradually in the direction indicated by the arrow shown in FIG. 4(A), that is, in a horizontal direction. As noted previously the slot 112 is slanted, so the actuator 103 is gradually lifted upward.
By depressing the operating member 121 so that it is in contact with the substrate 111 the projection 124 moves to the position shown in FIG. 4(B), thus positioning the actuator 103 at a maximum high position and closing the contacts 105 of the jack portion 101. At this stage the strength of contact at the contacts 105 is at its greatest.
As thus described the conventional connector, through the use of an LIF connector tool, operates by moving the actuator 103 up and down with respect to the substrate 111 so as to adjust the strength of contact between the contacts 105 of the jack portion 101 and the pins of the plug not shown in the diagram. It should be noted that it is normally not necessary to perpetually mount the LIF connector tool depicted in FIG. 3 on the substrate 111. Instead, it is sufficient to mount the LIF connector tool on the substrate 111 only when inserting or removing the plug pins.
However, conventionally a tool for inserting and removing the plug pins is mounted on the substrate together with the LIF connector jack portion, with the result that the load surface area of the connector increases substantially.
Moreover, even an arrangement whereby the above-described tool is only mounted when inserting and removing the plug pins is unsatisfactory because space must be secured for such insertion and removal and no reduction in load surface area is achieved as a result.